Lawn Equipment Parts
How To Repair Mower Blade That Will Not Cut
If your mower seems to be functioning properly but is not cutting grass, inspect the blade to see if it has been installed upside down. The crankshaft that the mower blade is attached to can only rotate in one direction, so the blade must be installed correctly so that the sharpened cutting edge of the blade is facing the right way. Most blades will have a stamp or some sort of wording on them to indicate which side should face up or down. All blades will always have a bevel or a curve in them, which will point up towards the mower deck when properly installed. When tilting the mower on its side to inspect the blade, make sure to tilt the mower so the carburetor is on the higher side so as not to force oil out of the crankcase and into the carburetor or exhaust.
If when your mower is running you detect an uncharacteristic or increasingly strong vibration or loud noise coming from the underside of the engine, the mower blade may not be secured properly and could possibly be coming loose. If you believe this is happening, shut the mower off immediately. The blade is held onto the underside of the engine with a bolt attaching directly to the crankshaft. If this bolt is not fully tightened it may slowly wiggle loose from the vibration of the engine while in use. It is important to always ensure that the blade is properly secured to the crankshaft so that it does not come loose or threaten to detach from the mower while it is spinning.